This is a continuation-in-part application to patent applications Ser. No. 208,739 entitled "Three-In-One Flowmeter" filed on Jun. 20, 1988 and Ser. No. 368,406 entitled "Mass-Volume Flowmeter" filed on Jun. 19, 1989.
In contrast to flowmeters of the present day technology which measure only one of the two flow rates, i.e., the mass flow rate or the volume flow rate, the flowmeters of future technology will measure the mass and volume flow rates as well as the density of media. The three-in-one flownmeters providing all of the three flow variables will cost slightly more than the present day flowmeters measuring only one of the three flow variables and, consequently, there is little doubt that the future flowmeter market will be dominated by one or other types of three-in-one flowmeters.